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The 1996 Oman cyclone (also known as Cyclone 02A) was a tenacious and deadly system that caused historic flooding in the southern Arabian Peninsula. It originated from a disturbance in the Gulf of Aden, the first such tropical cyclogenesis on record. After moving eastward, the system interacted with the monsoon trough and became a tropical storm on June 11. Later that day, it turned toward Oman and struck the country's southeast coast. It weakened over land, dissipating on June 12, although it continued to produce rainfall – heavy at times – over the next few days. Offshore Oman, the storm's rough waves disabled an oil tanker and damaged a fishing boat, killing one person in the latter incident. Striking Oman, the storm produced significant rainfall totals well above the monthly average, peaking at in the Dhofar region. Strong winds where the storm moved ashore damaged buildings and the local water plant. The rains washed out roads and isolated villages, killing two people due to drowning in Al-Ghubra. However, the effects were more severe in Yemen, where the floods were considered the worst on record. The storm produced the heaviest rainfall in 70 years, reaching in Ma'rib. Flood waters washed away or damaged of roads and 21 bridges, some of them dating back 2,000 years to the Roman era. The storm washed away the topsoil or otherwise wrecked of crop fields, accounting for US$100 million in agriculture damage. At least 1,820 houses were destroyed, many of them built on wadis, or dry river beds. Overall damage was estimated at US$1.2 billion, and there were 338 deaths in Yemen. The World Bank assisted in a project to rebuilt the damaged infrastructure in Yemen and to mitigate against future floods. ==Meteorological history== On May 31, a weak circulation persisted over the warm waters of the Gulf of Aden between Yemen and Somalia. Its origins were unknown, possibly the convergence of the sea breeze along the coast of Somalia with the monsoon flow. The system produced convection, or thunderstorms, along both coasts of the body of water. As it moved east-northeastward along the coast of Yemen and Oman, the disturbance brought dry air from the north, which decreased the convection. It moved farther offshore on June 7 into the open Arabian Sea, where it interacted with the south-west monsoon and developed more convection. The area of thunderstorms persisted about 1,480 km (920 mi) northeast of Somalia by June 9. It became circular as the circulation became more defined, fueled by the instability from the monsoon trough.〔 Wind shear was expected to prevent significant development, although the system organized enough that the Joint Typhoon Warning Center issued a tropical cyclone formation alert on June 10.〔 On the next day, the agency initiated advisories on Tropical Cyclone 02A about 160 km (100 mi) from the Oman coastline.〔 This marked the first occasion that a tropical cyclone originated from a system in the Gulf of Aden.〔 After becoming a tropical storm, the system's structure became more aligned as it developed an anticyclone aloft. Fueled by water temperatures of , the cyclone intensified further.〔 At 03:00 UTC on June 11, the Omani city of Fahud recorded sustained winds of 75 km/h (45 mph), and a station on Masirah Island recorded a pressure of . On this basis, the JTWC estimated that the storm attained peak winds of 75 km/h (45 mph).〔 However, a nearby ship reported sustained winds of 85 km/h (50 mph), and the well-defined structure on satellite imagery suggested winds as strong as 120 km/h (75 mph).〔 Moving northwestward, the cyclone made landfall around 09:00 UTC on June 11 about 130 km (80 mi) southwest of Masirah Island in southeastern Oman, at a location named Ras Madrakah.〔 It quickly weakened over the desert terrain and dry air, and the circulation dissipated by June 12 over the central portion of the country.〔 However, the remnants turned to the southwest, steered by a northerly flow. It entered the Rub' al Khali, or Empty Quarter, of Saudi Arabia late on June 12, and continued slowly westward. The storm's interaction with the monsoon brought the intertropical convergence zone northward into Oman and Yemen, bringing unusually heavy rainfall until the system gradually wound down.〔 The IMD – the official warning agency for the basin – did not track the cyclone. In general, tropical cyclone forecast models failed to predict that the storm would form.〔 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「1996 Oman cyclone」の詳細全文を読む スポンサード リンク
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